ISSUE:

Some vehicles equipped with a 6.0L engine may require the cylinder head to be removed and a new cylinder head flatness check has been developed. This check is to ensure the component part is not out of factory specification prior to installation. The surface quality (finish) of the cylinder head gasket surface is machined to close tolerances which enable an effective sealing joint for the multi-layered steel (MLS) gasket.

ACTION:

Follow the Service Procedure steps to verify cylinder head flatness meets new specification.

SERVICE PROCEDURE

Preparation

Ensure all head gasket surfaces are clear of any gasket debris, RTV, oil, and coolant using Motorcraft® Silicone Gasket Remover (ZC-30) and Motorcraft® Metal Surface Prep (ZC-31). Use a lint free rag to mop up the deck surfaces. Shop vacuums are unacceptable for mop up as the surface cleaning material is volatile. The head surface must be clean and dry before running a flatness check

NOTE:

DO NOT MEASURE FLATNESS IN THE LENGTHWISE (LONGITUDINAL) DIRECTION! THE OVERALL END-TO-END FLATNESS OF THE CYLINDER HEAD IS NOT AS CRITICAL AS THE LOCALIZED FLATNESS CHECKS. LONGITUDINAL MEASUREMENTS ARE NOT AN ACCURATE INDICATION OF FLATNESS WHEN INSTALLED DUE TO THE CLAMP LOAD OF THE HEAD TO BLOCK BOLTED ASSEMBLY. THE BOLTED CONDITION CAUSES AN OVERALL FLATNESS CONDITION THAT DIFFERS FROM THE FREE STATE CONDITION OF THE HEAD.

Use a straight edge that is calibrated by the manufacturer to be flat within 0.0002 inches (0.005 mm) per running foot length. For example, the straight edge may be 24″ (61 cm) long. That means the machined edge must be flat within 0.0004″ (0.010 mm) from end to end

Use Snap-On straight edge, Precision, 24″ Stock number: GA438A or equivalent. All Ford dealers were provided this precision straight edge in 2001, it came in a red plastic case and is marked Central Tools

Use Snap-on Feeler Gauge stock number FB310B (.001″ through .015″) or equivalent. The feeler gauge must contain a .002″ blade

Special care is required to ensure the tool is not damaged in handling or storage. A straight edge should be stored by hanging it vertically, or in its supplied protective case. Be sure the machined surface is free of nicks and dents. If these properties are found, the cost of tool re-calibration most likely will exceed the cost of a new straightedge. Machine shops may not be able to hold the specified tolerance within the original cost of the straight edge

When checking for flatness, avoid running the feeler gauge butt end against the straight edge. This action will curl or warp the feeler gauge leaf and prevent entry under the straight edge. Erroneous readings will result. Instead, lay the feeler gauge leaf on the point of inspection, placing the straight edge on top of the leaf. If the leaf is pulled out easily or is loose, the head is locally out of flat

13 Point Check System

Use the following 13 point check system to identify cylinder head flatness. Depressions in the cylinder head that are greater than 0.002″ deep do not seal properly when using a MLS gasket.

To measure the cylinder head for flatness, set the 0.002″ feeler gauge on each measurement point with the straight edge transverse or perpendicular to the head. (Figure 1) Set the straight edge on top of the feeler gauge.

NOTE:

INSPECT POINTS 2 AND 3 FIRST. THESE TWO POINTS ARE THE MOST SUSCEPTIBLE TO FAIL.

While protecting the straight edge from tipping over, allow the straight edge to stand up on top of the feeler gauge.

Pull lightly on the feeler gauge.

The head is locally out of flat, and needs to be replaced if the 0.002″. feeler gauge is loose or slides out from under the straight edge.

NOTE:

DO NOT MACHINE THE HEAD.

Repeat for all 13 points. (Figure 1)

PART NUMBER

PART NAME

ZC-30

Motorcraft® Silicone Gasket Remover

ZC-31

Motorcraft® Metal Surface Prep

WARRANTY STATUS:

Eligible Under Provisions Of New Vehicle Limited Warranty Coverage

DEALER CODING

BASIC PART NO.

CONDITION CODE

6049

14

Figure 1 – Article 06-21-10

NOTE: The information in Technical Service Bulletins is intended for use by trained, professional technicians with the knowledge, tools, and equipment to do the job properly and safely. It informs these technicians of conditions that may occur on some vehicles, or provides information that could assist in proper vehicle service. The procedures should not be performed by “do-it-yourselfers”. Do not assume that a condition described affects your car or truck. Contact a Ford, Lincoln, or Mercury dealership to determine whether the Bulletin applies to your vehicle. Warranty Policy and Extended Service Plan documentation determine Warranty and/or Extended Service Plan coverage unless stated otherwise in the TSB article. The information in this Technical Service Bulletin (TSB) was current at the time of printing. Ford Motor Company reserves the right to supercede this information with updates. The most recent information is available through Ford Motor Company’s on-line technical resources.